In Tokyo the central bank said it would increase its asset purchase programme by five trillion yen ($62 billion) to 70 trillion yen, its latest move to breathe life into the world's third-largest economy.

The move, following a one-day policy meeting, came hours after data showed inflation at just 0.2 percent -- almost solely due to rocketing energy prices -- while consumer spending remained weak and unemployment static.

Markets reacted favourably to the plan initially, with the dollar and euro jumping against the yen, and the Nikkei surging into positive territory. But the euphoria soon subsided.

Regionally, dealers were also taking a cue from the United States and Europe.

The US National Association of Realtors reported Thursday that pending home sales rose in March, providing a lift to investors amid hopes of a recovery in the crucial sector.

The group said its pending home sales index -- which represents contracts signed but not closed -- rose 4.1 percent in March to 101.4, its highest level since April 2010 when it hit 111.3. It added that on a 12-month basis, pending sales were up 12.8 percent.

Also on Thursday the Commerce Department said new jobless claims remained at high levels after edging up in recent weeks.

It said 388,000 people made claims in the week to April 21, compared to a revised 389,000 the previous week and a four-week moving average of 381,750, adding to concerns about Washington's battle against unemployment.

"This continues the mixed signals the US economy is throwing up as investors seek guidance on how resilient its economic recovery is," Justin Harper, market strategist at IG Markets Singapore said in a note.

Further denting confidence was news that Standard & Poor's had cut Spain's debt rating by two notches as the country struggles to bring down its huge public deficit amid concerns it could lead to a Greece-style crisis in the eurozone.

S&P reduced Madrid's rating to BBB-plus and added a negative outlook, saying it expected the economy to shrink this year and next.

It also warned that the government's budget situation was worsening and its banks would likely rely increasingly on official sources for funding as they grapple with piles of bad loans, especially in real estate.

"The downgrade should not be entirely surprising but it would further weigh on the fragile sentiment in (the) eurozone, which had undergone a series of negative political events in Holland and France earlier this week," Credit Agricole said in a note to clients.

In early European trade the dollar eased to 80.64 yen from 80.96 yen in New York late Friday.

The euro was changing hands at $1.3222, down from $1.3240, while it fell to 106.61 yen from 107.18 yen.

On oil markets, New York's main contract, West Texas Intermediate crude for delivery in June was down 35 cents to $104.20 per barrel while Brent North Sea crude for June shed 29 cents to $119.63.

Gold was at $1,655.50 an ounce at 1110 GMT, compared with $1,647.04 late Thursday.